April 25, 2014 – After weeks of no comment, the Chicago Department of Transportation came clean on Friday about a lull in construction of the Chicago Riverwalk between State and LaSalle Streets.

“The project had some delays,” said construction manager Oswaldo Chaves in an update on Friday to neighbors of the Riverwalk. “Large scale construction projects of this kind use specialized equipment and from time to time that equipment malfunctions.”

According to Chaves, the mechanical hammer – that pounds steel piles into the ground – broke down. A replacement hammer was delivered to the construction site and put into operation on Friday.

(Left) Close view of a large yellow hammer driving a vertical “H pile” steel beam into the riverfront west of State Street on March 28. Encased in more solid ground, the pile will support the weight of the Riverwalk. (Click on image to view larger version.)

Work beneath the bridges at State, Dearborn, and Clark Street, which will require the south leaf of each bridge to be raised for seven days at a time, has been rescheduled. The first of the bridge closures is now planned for the week of May 12.

“The lack of production in the State Street block had a ripple effect on the schedule for future activities for the Riverwalk project,” said Chaves.

While a bridge is up, crews will work 24 hours a day. Most of the machinery noise, similar to the engine of a large truck that is accelerating, will be heard during the day, promised Chaves in March.

Installation of H piles and longer sections of sheet piles will continue and, says Chaves, should be finished by May 23. Workers will also continue removing old concrete.

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